Various existing thin-film devices including thin-film resistance elements have been provided, for example, as disclosed in Patent Document 1 (identified below). For example, an existing thin-film device 500 illustrated in FIG. 7 includes an integrated circuit 502 formed on a semiconductor substrate 501, a plurality of electrode pads 503 arranged on the integrated circuit 502, and a resin layer 505 formed on passivation films 504 between the electrode pads 503. The resin layer 505 is made of polyimide resin, epoxy resin, or the like, and through-holes are provided in the resin layer 505 at positions overlapping with the electrode pads 503. Furthermore, rewirings 507 connected to the electrode pads 503 with a barrier metal layer 506 interposed therebetween in the through-holes are formed on the resin layer 505. As further shown, a thin-film resistance element 508 is provided at a position interposed between the rewirings 507 on the resin layer 505.
In the thin-film device 500 illustrated in FIG. 7, the thin-film resistance element 508 includes the barrier metal layer 506 and a seed layer 509 laminated on the barrier metal layer 506. The barrier metal layer 506 can be made from Ti, TiN, Ni, or the like, and is provided in order to improve close contact property between the electrode pads 503 and the rewirings 507. The seed layer 509 functions as an electrode when the rewirings 507 are formed by a plating technique, and is made of Cu, Al, or the like. The film thicknesses of the barrier metal layer 506 and the seed layer 509 are appropriately controlled to adjust a resistance value of the thin-film resistance element 508.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2009-267248.
When the thin-film device 500 illustrated in FIG. 7 is heated in a heat cycle when being mounted, and so on, on another substrate or the like, bending stress is applied to the thin-film resistance element 508 due to expansion and the like of the resin layer 505. This effect results in a risk of breakage of the thin-film resistance element 508.